一种三维图形定位技术及误差评定方法

Three-Dimensional Graphical Location Technology and Method of Evaluating the Error

在视觉检测技术的应用中,视觉传感器在三维坐标系统中的定位是重要而复杂的关键技术．为此,在汽车整体形位误差测量中,采用新颖的图形定位方法来定位数十个视觉传感器．该方法的要点在于,只要把视觉传感器采集到的车身特征图形与计算机屏幕上预先设定的标准图形重合,即完成了对传感器的定位．文中介绍了图形定位技术的原理,重点论证了图形定位精度的评定方法．经过多种方案的比较,最终采用了最小二乘法综合误差评定的方法．通过理论分析和实验验证,确定了三维图形定位的重复性误差可达0．035mm,优于其他方法所达精度的3 倍,且定位速度提高了十几倍．

In the appliancation of vision inspect technology, it is complicated and important to locate the vision sensor in three-dimension coordinate system. To measure the error of automotive figure and location, the numbers of sensors are positioned through adjusting the characteristic figure of the auto gathered by the vision sensor to the preconcerted standard figure in the computer. The graphical location technology is presented, especially the methods of evaluating the repeatability. Commpared with other schemes, the least square method is adopted. Theory analysis and a mass of experiments indicate that the repeatability of three-dimensional graphical location technology is 0.035 ram, which is 3 times less than other methods, and the rate of location is increased more than ten times.